DataStax: 7 Deadly Sins for Cassandra Ops

DataStax: 7 Deadly Sins for Cassandra OpsSlideShare Explore YouSuccessfully reported this slideshow.We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.DataStax: 7 Deadly Sins for Cassandra OpsUpcoming SlideShareLoading in …5×1 1 of 23 Like this presentation? Why not share!0 Comments6 LikesStatisticsNotesChandan Kumar , Principal Software Engineer at Symantec at Symantec Ophir Radnitz , Senior Software Architect at VMware Pramod Sivaraju griever9 Eiti Kimura , IT Development Coordinator at Movile at Movile Show MoreNo DownloadsNo notes for slide1. 7 Deadly Sins for Cassandra Ops
 Rachel Pedreschi
 DSE Evangelist, Datastax2. 2© 2015. All Rights Reserved.3. Lust 3© 2015. All Rights Reserved. #1 USE THE SIMPLE SNITCH4. So many snitches… 4© 2015. All Rights Reserved. • SimpleSnitch • RackInferringSnitch • PropertyFileSnitch • GossipingPropertyFileSnitch • Ec2Snitch • Ec2MultiRegionSnitch • GoogleCloudSnitch • CloudstackSnitch5. Switching snitches 5© 2015. All Rights Reserved. If the topology of the network has changed: -Shut down all the nodes, then restart them. -Run a sequential repair and nodetool cleanup on each node. DOWNTIME ALERT!!!!6. Greed 6© 2015. All Rights Reserved. #3 NOT UNDERSTANDING REPAIR7. Repair options 7© 2015. All Rights Reserved. repair (default, check your version!) repair -pr (only repair the primary range) repair -inc (only new data that has not previously been repaired) sequential repair (creates snapshots) parallel repair uses replica not being repaired8. Envy 8© 2015. All Rights Reserved. #3 CHOOSE THE WRONG COMPACTION STRATEGY FOR YOUR WORKLOAD9. Sized Tiered 9© 2015. All Rights Reserved. SST1 SST1 SST2 SST1 SST2 SST3 SST1 SST2 SST3 SST4 SST5 FLUSH FLUSH FLUSH FLUSH COMPACT SST5 SST6 SST5 SST6 SST7 SST5 SST6 SST7 SST8 SST5 SST10 FLUSH FLUSH FLUSH SST5 SST6 SST7 SST8 FLUSH SST9 COMPACT Compacts a set number of SSTables into a single, larger SSTable10. Leveled 10© 2015. All Rights Reserved. Level 0 Level 1 10 Level 2 100 Level 3 1,000 Level 4 10,000 Level 5 100,000 … Level 6, 7, etc.11. Date Tiered 11© 2015. All Rights Reserved. https://labs.spotify.com/2014/12/18/date-tiered-compaction/12. Gluttony 12© 2015. All Rights Reserved. #4 CHOOSING THE WRONG HARDWARE13. 13© 2015. All Rights Reserved. CPU RAM DISK14. 14© 2015. All Rights Reserved. • 2 socket, ECC memory • 16GiB minimum, prefer 32-64GiB, over 128GiB and Linux will need serious tuning • SSD where possible, Samsung 840 Pro is a good choice, any Intel is fine • NO SAN/NAS, 20ms latency tops • if you MUST (and please, don’t) dedicate spindles to C* nodes, use separate network • Avoid disk configurations targeted at Hadoop, disks are too slow15. Sloth 15© 2015. All Rights Reserved. #5 NOT TUNING YOUR OS16. /etc/rc.local 16© 2015. All Rights Reserved. ra=$((2**14))# 16k ss=$(blockdev --getss /dev/sda) blockdev --setra $(($ra / $ss)) /dev/sda echo 128 > /sys/block/sda/queue/nr_requests echo deadline > /sys/block/sda/queue/scheduler echo 16384 > /sys/block/md7/md/stripe_cache_size17. /etc/sysctl.conf 17© 2015. All Rights Reserved. fs.file-max = 1048576 vm.max_map_count = 1048576 net.core.rmem_max = 16777216 net.core.wmem_max = 16777216 net.ipv4.tcp_rmem = 4096 65536 16777216 net.ipv4.tcp_wmem = 4096 65536 16777216 vm.swappiness = 118. Wrath 18© 2015. All Rights Reserved. #6 OVER OR UNDERSIZING YOUR JVM19. G1 or CMS? 19© 2015. All Rights Reserved. • Cassandra 8150 vs 7486 • Larger heap? Look into using G1 • Read the Docs • Test, test and did I mention, test?20. Pride 20© 2015. All Rights Reserved. #7 NOT STRESS TESTING21. cassandra-stress .yaml (>= 2.1) 21© 2015. All Rights Reserved. 1. DDL – for defining your schema 2. Column Distributions – for defining the shape and size of each column globally and within each partition 3. Insert Distributions – for defining how the data is written during the stress test 4. DML – for defining how the data is queried during the stress test22. Recommended Sessions 22© 2015. All Rights Reserved. DataStax Making Cassandra Fail (for effective testing) 3:30 Thursday Ballroom H Pythian Manage your compactions before they manage you 4:20 Ballroom H The Last Pickle Steady State Data Size with Compaction, Tombstones, and TTL 4:20 Great America #2 Wednesday Crowdstrike, Inc. Real World DTCS For Operators23. Thank you @RachelPedreschiRecommendedTest Prep: PSATOnline Course - LinkedIn LearningFlipping the ClassroomOnline Course - LinkedIn LearningPowerPoint for Teachers: Creating Interactive LessonsOnline Course - LinkedIn LearningBattery Ventures: Simulating and Visualizing Large Scale Cassandra DeploymentsDataStax AcademyDataStax: Old Dogs, New Tricks. Teaching your Relational DBA to fetchDataStax AcademyDataStax: How to Roll Cassandra into Production Without Losing your Health, M...DataStax AcademyCassandra Core ConceptsJon HaddadCassandra 3.0 AwesomenessJon HaddadDataStax & O'Reilly Media: Large Scale Data Analytics with Spark and Cassandr...DataStax AcademyCrash course intro to cassandraJon Haddad×Share Clipboard×LinkPublic clipboards featuring this slideNo public clipboards found for this slideSelect another clipboard×Looks like you’ve clipped this slide to already.Create a clipboardYou just clipped your first slide!Clipping is a handy way to collect important slides you want to go back to later. Now customize the name of a clipboard to store your clips.